Lenovo 92P0991 Household Battery Battery And Power Supply

Compatible Models: IBM ThinkPad R40 Series and R40e Series, Evesham Voyager C720DC laptop and more.

This small battery is commonly used in many IBM THINKPAD SERIES R40 and R40e laptop computers. Our battery is a replacement for the CMOS battery mentioned. This battery can be used in many IBM ThinkPad R40 Series, etc laptop computers which use a 3.0 Volt clock battery.

CMOS & Clock Backup batteries perform an important function when the power is turned off; the CMOS battery maintains the time and date, thus insuring their accuracy when the system is once again restarted. Also important, the battery saves the computers BIOS set-up configuration, so the system can be efficiently rebooted once it is switched on again. For example, the computer knows what type of hard drive it is booting from etc. These batteries are variously known as CMOS batteries, Real Time Clock (RTC) batteries, PRAM batteries or simply internal batteries.